Candice Autry

August 16, 2006March 26, 2021

Candice Autry, August 16, 2006

NOAA Teacher at Sea
Candice Autry
Onboard NOAA Ship Thomas Jefferson
August 7 – 18, 2006

Mission: Hydrographic Survey
Geographical Area: Northwest Atlantic
Date: August 16, 2006

“Experiences on the Fast Rescue Boat”

TAS Candice Autry prepares to use the CTD instrument which collects water information related to conductivity, temperature, and depth. — Candice Autry prepares to use the CTD instrument which collects water information related to conductivity, temperature, and depth.

Science and Technology Log

Today I had the opportunity to go out on the Fast Rescue Boat (FRB) to use the conductivity, temperature, depth (CTD) instrument in various places in the harbor. The CTD looks like a simple white tube; however, the capabilities of the CTD are far from simple! This devise provides essential data for scientists. Three of us boarded the small FRB, loaded the CTD, and were off to our locations. The first observation noted is that being on the fast rescue boat is a different boating experience compared to the launches and the THOMAS JEFFERSON. The “fast” part of the description is fitting; the boat moves quickly! The main function of the CTD is to collect data about how the conductivity and temperature of water changes relative to depth. Conductivity and temperature information is important because the concentration of the salt of the seawater can be determined by these two changing variables.

Candice Autry holds the CTD instrument. We collected information from three locations; once in the morning and then again in the afternoon.

The CTD devise can also help surveyors determine the speed of sound in the water. The information from the CTD is used in conjunction with multi-beam sonar providing accurate data about the depths of obstructions on the seafloor. The metal frame seen in the picture on the outside of the mechanism is called a rosette. We attached a rope to the rosette of the CTD, turned it on to collect data, held the devise in the water for two minutes for adjustment, then lowered the instrument down to the bottom of the seafloor. Once the CTD hits the bottom of the seafloor, the rope is pulled back up, the devise is put back into the fast rescue boat, turned off, and it is off to the next location to collect data. We deployed the CTD in three different locations in the morning and three different locations in the afternoon. At each place where data collection occurred, the location was recorded by using a global positioning system. Back on the THOMAS JEFFERSON, the information that the CTD collected is downloaded to a computer where specialized software is used to understand the data.

Personal Log

All of the experiences on the THOMAS JEFFERSON have been interesting and fun. Tomorrow I will be helping some of the crew on the deck of the ship. Exposure to saltwater often causes rust to occur; a ship requires constant maintenance! I am also realizing that this adventure will be over soon, with less than two days left. Until tomorrow…..

Senior Surveyor Peter Lewit shares the chart used as a guide for the launches to collect data. The red lines in the white area of the chart represent the paths the launches took to collect data using side scan sonar and multi-beam sonar technologies. — Surveyor Peter Lewit shares the chart used to collect data. The red lines in the white area represent the paths the launches took.

August 15, 2006March 26, 2021

Candice Autry, August 15, 2006

NOAA Teacher at Sea
Candice Autry
Onboard NOAA Ship Thomas Jefferson
August 7 – 18, 2006

Mission: Hydrographic Survey
Geographical Area: Northwest Atlantic
Date: August 15, 2006

Crew members prepare the launches to collect data using side-scan and multi-beam sonar

Weather
AM: SW winds 15-20 knots, Seas 1-2 feet
PM: W winds 10-15 knots, Seas 1-2 feet Chance of showers

Science and Technology Log: Data Collection Begins!

We have made it to our destination after a thirty-hour journey. It is exciting to get started with data collection, I am curious what is on the bottom of a busy harbor. After a brief safety meeting that kicks off the morning, we prepare to go out on the launches to begin the process of making a chart that will provide information about obstructions in navigable waters. The teamwork of the crew of the THOMAS JEFFERSON is inspiring to watch, each with a specific duty communicating and working together so that launches are safely deployed. Today two launches will collect data using side-scan sonar and multi-beam sonar technologies.

The launch is ready to start collecting data. Typically, a launch has a driver, another person to look out for water traffic, and a surveyor who observes the data being collected and who manipulates the computers connected to the "fish" below the launch. — The launch is ready to collect data. Typically, a launch has a driver, a person to look out for water traffic, and a surveyor who observes the data being collected and manipulates the computers connected to the “fish” below the launch.

Bernard Pooser behind the wheel of the launch. The route he drives in the harbor is very specific, and he must follow careful ‘driving lines’ that the surveyor also sees on one of the four computer screens inside of the launch. This job is much easier said than done, a real challenge! — Bernard Pooser driving the launch in the harbor. The route is very specific and he must follow careful ‘driving lines’ that the surveyor also sees on one of the four computer screens inside of the launch. This job is much easier said than done!

Senior Surveyor Peter Lewit prepares to collect data utilizing side scan sonar. Side-scan sonar provides a picture that shows light and dark images that provide high-resolution images of obstructions on the seafloor. — Senior Surveyor Peter Lewit prepares to collect side scan sonar data, which provides light and dark high-resolution images of obstructions on the seafloor.

The launch I am on today utilizes side-scan sonar, which incorporates sound navigation and ranging that is used for searching for objects on the seafloor. This technology transmits sound energy, which sends a beam from the “fish” (the instrument underneath the launch) that bounces off the seafloor and other objects. Once the sound energy hits the floor, it then bounces back to the fish in the form of an echo. These beams are sent in a fan-shaped pattern that sweeps the seafloor from underneath the launch to approximately 75 meters from either side of the boat (although distances can reach 100 meters). The strength of the echo is recorded as a “picture” that can be seen on a computer screen. If there is an object on the bottom of the seafloor, such as a protrusion, the return signal will be strong and will create a dark image on the screen. If the return signal has a weak return, then the image on the computer will look light. A tire on the seafloor, or a barge that has sunk is easily seen and depicted! These images are fascinating.

Surveyor Doug Wood observes computer screens where data is being collected. The green triangle is showing multi-beam sonar data. — Surveyor Doug Wood observes computers where data is being collected.

The benefit of side-scan sonar allows for high-resolution of what is on the seafloor. The only drawback of side-scan sonar technology is that the depth of these obstructions cannot be ascertained. Determining the depth of an obstruction is where multi-beam sonar is applied. Multi-beam sonar utilizes fan-shaped sonar that records depths. This is done by recording the time it takes for the acoustic signal to travel from the receiver to the seafloor (or object on the seafloor) back to the receiver. The receiver is often referred to as a transducer. The multi-beam sonar transducer is attached underneath the launch. The combination of side scan sonar and multi-beam sonar create for specific data that can be shared so that navigable waters are safe.

Personal Log: “I have my sea legs!”

I must admit I was a bit nervous about being seasick! Our thirty-hour journey was difficult for me for only about three hours, right at the beginning of the trip. I am very happy for a short experience with seasickness! After getting my sea legs, it is interesting to realize that one can adapt quickly. Often I felt like I was being rocked to sleep as we made our way to our destination through the waves of the ocean. After being on a ship for a couple of days, experiencing land is an interesting sensation. I missed moving around on water and felt as if I were on water even though I was on land! I do not really miss being on land at all.

NOAA Teacher at Sea, Candice Autry, enjoys pudding while taking a break from observing data collection using side-scan sonar. The Statue of Liberty is in the background! — Candice Autry, enjoys pudding while taking a break from observing data collection. The Statue of Liberty is in the background!

August 12, 2006March 26, 2021

Candice Autry, August 7-12, 2006

NOAA Teacher at Sea
Candice Autry
Onboard NOAA Ship Thomas Jefferson
August 7 – 18, 2006

Mission: Hydrographic Survey
Geographical Area: Northwest Atlantic
Date: August 7 -12, 2006

“Ships have many pieces of complicated equipment!”

The NOAA Ship THOMAS JEFFERSON awaits a necessary part for the crane that lifts the fast rescue boat, then we set sail — The NOAA Ship THOMAS JEFFERSON awaits a part for the crane that lifts the fast rescue boat, then we set sail

Personal Log

Hello, greetings from Teacher at Sea Candice Autry. I teach science to middle school students at a wonderful school called Sheridan School in Washington, DC. I have been given the great opportunity to sail with the crew on the NOAA Ship THOMAS JEFFERSON. Our cruise has been delayed several days due to unforeseen problems with some of the complex and necessary equipment on the ship. It is important to be flexible with any kind of change, so these past few days have given me the opportunity to explore the ship as we wait for final repairs. The objectives of this particular ship primarily involve hydrographic surveys. Hydrography is the science that has to do with measuring and describing physical characteristics of bodies of water and the shore areas close to land. Thanks to hydrographic surveys, ships, ferries, pleasure boats, and other vessels can safely navigate in busy waters without hitting any obstructions on the bottom of a harbor.

A functioning crane on the NOAA Ship THOMAS JEFFERSON lifts the necessary fast rescue boat (FRB) aboard. — A crane lifts the necessary fast rescue boat aboard.

Hydrographic surveys can also locate submerged wrecks in deep waters; examples include unfortunate events such as shipwrecks out at sea as well as plane crashes over the ocean. These surveys are done by using technology that involves side scan sonar and multi-beam sonar technology. The combination of these two types of technologies can create a clear picture of a barrier on the ocean floor and the depth of the obstruction.

The THOMAS JEFFERSON holds several smaller boats including two launches (one launch is visible in the picture, it is the gray boat) that have this sonar technology located underneath the vessel. The instrument that collects data is often called a “fish.” The data can be seen on a computer screen so that the surveyors can view the data being collected. Once we reach our destination, we will use these launches, one equipped with a fish that uses multi-beam sonar technology and the other with a fish that uses side scan sonar to create a chart of what is on the bottom of a very busy harbor!

Seaman Surveyors Doug Wood and Peter Lewit interpret hydrographic data in the survey room

One of the workrooms aboard the NOAA Ship THOMAS JEFFERSON.

A closer look at the navigational equipment on the bridge